Climate vulnerable countries have reacted with anger at moves by Saudi Arabia and India to quash a UN report that said it would be better to limit global warming to 1.5C above pre industrial levels rather than 2C.

The two countries moved late on Thursday at international talks in Paris to block attempts to reference the study’s findings in a proposed global climate change deal, due to be agreed at the end of next week.

Known as an “expert dialogue”, the study ran from 2013-2015 and was published by the UN in June.

It said that warming up to 1.5C would likely be “beyond the adaptive capacity of some people”, while noting that a lower warming goal this would require radical greenhouse gas cuts.

Sources said leaders in Riyadh and Delhi saw its findings as a direct threat to their economies, which rely heavily on oil and coal.

James Fletcher, St Lucia’s minister for sustainable development, energy, science and technology, described the efforts to kill the report’s findings as “very unfortunate” and promised to tackle the issue at ministerial meetings next week.

“I am not sure what is the thinking behind Saudi Arabia and India, what compelled them to take that position,” he told Climate Home.

“My technical officers came back distraught – it seems Saudi Arabia and India were against a sea swell of opinion that very much wanted 1.5C included in the discussion.”

Bill Hare from Climate Analytics, an advisor to St Lucia who observed Thursday’s discussions, said the move had created “deep anger” among a wide array of countries, including Bangladesh, the Philippines and Costa Rica.

“The issue was summarily blocked without a stated line of reasoning,” he said. India’s delegation to the Paris talks declined to comment.

Alden Meyer from the US Union of Concerned Scientists said it would be a “tragedy” if the report was binned. “It is a powerful piece of work,” he said.

Over 100 countries have now declared their support for the lower warming goal of 1.5C, with France and Germany the latest to signal their desire to see it referenced in a final Paris agreement.

“There is a sense of frustration at the adequacy of action so the response is to up the ante,” said Liz Gallagher from the E3G think tank.

In a statement Maldives envoy Thoriq Ibrahim, chair of the alliance of small island states (AOSIS) said the 1.5C was a “moral threshold” for his country.

Pa Ousman Jarju, Gambia’s director of water resources, said the target was not negotiable. “It is a matter of survival,” he said.

Some scientists say the 1.5C goal could already be out of reach due to the levels of greenhouse gases already emitted. Global average temperatures are already on course to pass 1C this year.

Professor Phil Jones from the Climatic Research Unit at the University of East Anglia told Climate Home the world could hit 1.5C in “about three decades time,” although stressed there were still uncertainties.

Dr Andy Wiltshire, a climate scientist at the UK Met Office said it was “plausible” that the world could see 1.5C by the 2040s.

“We’re not passed the point of commitment to 1.5 yet but we’re very close, so 1.5 is still technically feasible,” he said.

“However, emissions would have to peak urgently and decline very rapidly. Virtually all feasible scenarios consistent with the 1.5 target have fossil emissions peaking this decade but still rely on large amounts of negative emissions later in the century.”